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Date:   Sat, 14 May 2022 14:44:43 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Sami Tolvanen <samitolvanen@google.com>
Cc:     linux-kernel@vger.kernel.org, Josh Poimboeuf <jpoimboe@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>, x86@kernel.org,
        Catalin Marinas <catalin.marinas@arm.com>,
        Will Deacon <will@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Joao Moreira <joao@overdrivepizza.com>,
        Sedat Dilek <sedat.dilek@gmail.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        linux-hardening@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org, llvm@lists.linux.dev
Subject: Re: [RFC PATCH v2 05/21] cfi: Drop __CFI_ADDRESSABLE
Message-ID: <202205141444.0C1A3ABD1@keescook>
References: <20220513202159.1550547-1-samitolvanen@google.com>
 <20220513202159.1550547-6-samitolvanen@google.com>
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On Fri, May 13, 2022 at 01:21:43PM -0700, Sami Tolvanen wrote:
> The __CFI_ADDRESSABLE macro is used for init_module and cleanup_module
> to ensure we have the address of the CFI jump table, and with
> CONFIG_X86_KERNEL_IBT to ensure LTO won't optimize away the symbols.
> As __CFI_ADDRESSABLE is no longer necessary with -fsanitize=kcfi, add
> a more flexible version of the __ADDRESSABLE macro and always ensure
> these symbols won't be dropped.
> 
> Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

These macros were so fun to build, though! ;)

Reviewed-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook